Process of removing paint and varnish



Patented Jan. 8, 1946 rnocuss 0F REMOVING PAINT'AND VARNISH Robert E. Sadtler, Ridley Park, Pa., assignor of one-fourth to Ney W. Underwood, J12, Cleveland, Ohio No Drawing. Application June 21, 1943.

Serial No. 491,663

1 Claim. (01. 252-142) The present invention relates to paint and varnish removing compositions and more particularly it relates to such compositions containing anacardic acid such as cashew nut shell liquid.

The principal object of my invention is to provide an eflicient and economical paint and varnish removing composition which is adapted to be applied to a painted or 'varnished surface without injury to the base material on which the paint or varnish film is formed.

Another object of my invention is to provide an inexpensive paint or varnish remover containing anacardic acid as the active paint or varnish removing constituent thereof.

A further object of my invention is to provide a paint and varnish removing composition which is adapted to remove paint or varnish films in a minimum of time and at a minimum of expense. These and other objects of the present invention will be more readily apparent from a consideration of the following detailed specification in conjunction with the appended claims.

Cashew nut shell liquid varies in its anacardic acid content depending upon the methods of extraction utilized to separate the liquid from cashew shells. Thus, the usual form of commercial cashew nut shell liquid which is obtained in India by burning or roasting thewhole cashew nuts,,has a substantial portion of its 'anacardic acid content decarboxylated by the heat to which it is subjected and therefore contains only about 16% of anacardic acid. However, if the liquid is extracted from the shells by pressure or by solvent extraction, a cashew nut shell liquid may be obtained having an anacardic acid content of from about 60% to about 90%. The present invention contemplates the use of either form of cashew nut shell liquid, or of anacardic acid,

' as a paint and varnish removing material.

I have made the discovery that paint and varnish film's may be economically and effectively removed from any type of surface b applying to said painted or varnished surface, a coating or layer of cashew nut shell liquid of high or low anacardic acid content, or by applying anacardic acid thereto.

In practicing my invention, I apply cashew nut shell liquid of high or low anacardic acid content, or anacardic acid itself, to the painted or varnished surface by any suitable means, such as by brushing or spraying the liquid or acid onto the surface or by immersing the painted or varnished article in the liquid or acid. After asuitable period of time, usually about 15 to 20 minutes, the paint or varnish film will become dissolved or loosened sufficientl to be removed, as by scraping the surface. As cashew nut shell liquid and crude anacardic acid are somewhat vesicating in character, the user should wear gloves when handling and applying the liquid or acid.

The foregoing specification and description include the essential and distinctive thought of my invention, but it is to be distinctly understood that the same may be modified in various ways and/or combined with various other details without affecting the peculiar results obtained, and without departing from the spirit of the invention or the scope of the appended claim in which I intend to claim all the patentable novelty inherent in my invention.

1'; claim as my invention:

The process of removing a set film of the group consisting of paints and varnishes from solid surfaces which comprises applying a material selected from the group consisting of anacardic acid and cashew nut shell liquid to said film, permitting it to remain in contact with the coated surface until the film has disintegrated and then removing the disintegrated fllm from the surface.

I ROBERT E. ssmwa. 

